Bernstein-Mode Quasioptical Maser Experiment

Abstract

Experimental observations of coherent, millimeter-wavelength, higher-cyclotron-harmonic oscillations are reported for a system of an electron beam in a magnetic field traversing a Fabry-Perot resonator. The parameters of the experiment tend to support the interpretation that the strong multiple-harmonic interaction results from mode conversion of short-wavelength electrostatic waves (Bernstein modes) to long-wavelength electromagnetic resonator modes at the beam boundary.